If you own a Bosch dishwasher, you’re undoubtedly already familiar with using the front control panel, but sometimes your washer will display an error code on this panel. These error codes don’t always mean that your dishwasher’s broken, and you need to rush out and buy a new one.
On the contrary, oftentimes, these errors are caused by fairly simple issues that can be rectified with a bit of general maintenance. One of the most common error codes to occur is the E24 error, which means that water isn’t able to drain away from the machine.
In this article, I’ll explain exactly what causes this problem and give you all the methods you need to fix it so you can get rid of this error code.
Causes of Bosch Dishwasher Error Code E24
While this error code informs us that the washer can’t drain water, what it doesn’t tell us is exactly what has caused the problem, which can make fixing it a challenge.
So let’s first go through all the reasons why your washer can’t drain so you can better diagnose what’s happening and get a better sense of what needs fixing.
1. The Drain Hose is Blocked
Often when water cannot drain from your washer, it means that the drain hose has become blocked up and is causing water to sit in the machine. Bosch dishwashers dispose of the dirty water by running it to the disposal pipe through the drain hose.
Over time, this drain hose can clog with bits of food debris, grease, and soap, eventually preventing the water from draining. The hose must be disconnected and thoroughly cleaned to drain the water.
2. The Filter is Clogged
There is a filter that the dishwasher water must pass through before it drains away, which is designed to catch as much food particulate as possible so it doesn’t end up getting into the drain hose and clogging it up.
This filter should be cleaned as part of your regular dishwasher maintenance (ideally once every 2 weeks); otherwise, it will become blocked and cause the washer not to drain properly.
3. The Knock-Out Plug hasn’t been Removed
If you recently installed a new dishwasher or garbage disposal, the installer may have forgotten to remove the knock-out plug.
As the name might suggest, the knock-out plug is just a simple piece of plastic that covers holes during transport to keep things safe, but it’s supposed to be knocked out once the installation is complete.
If your installer forgot to go it, the remaining knock-out plug will still be there and prevent the water from draining away. So you’ll need to locate the knock-out plug and knock it out yourself.
4. A Bug or Glitch has Occurred
Bosch dishwashers are great because they give you so many options to customize your wash preferences to exactly what you need.
However, this heavy integration of computer systems and touchscreen panels means that from time to time, they can run into errors or glitches, which may trigger the E24 error with no real cause behind it.
The good news is that these bugs can be easily fixed by performing a hard reset or power cycle.
5. The Inlet Hose has been Kinked or Pinched
If your dishwasher’s hose has become kinked or pinched, then the water may not be able to flow into or away from the dishwasher, causing it to remain inside the machine.
Usually, this happens because the dishwasher has been pushed against the wall too hard, causing the pinch. If this is the case, the hose must be arranged more optimallyย so the water can flow through it properly.
In some rare cases, the hose may be damaged or cracked, which poses a risk of leaking; in this scenario, the hose should be entirely replaced.
6. The Siphon Connection is Not Properly Sealed
The siphon connection, sometimes called the ‘air gap‘, is designed to prevent water from flowing back into the machine by creating this gap between when the water exits the drain hose and then enters the disposal drain of your home.
However, if this air gap isn’t sealed correctly, it may allow water to back up into the washer and cause this E24 code error to occur. The siphon connection will need to be inspected and fixed accordingly.
7. The Pump Cover is Loose
If the dishwasher drain pump cover is loose, it will allow more water to flow to the drain pump than needed which then overloads the pump.
This cover must be located and tightened so the correct volume of water flows into the pump.
How to Fix Bosch Dishwasher Error Code E24
Now that you’ve established exactly where the possible blockage points lie on your dishwasher, it’s time to get them unblocked and eliminate this error code once and for all!
1. Unblock the Drain Hose
The first thing you need to do is unblock the drain hose; while there are many ways to do this, the easiest and most effective is using a baking soda and vinegar cleaning solution.
- Start by turning the water supply to the dishwasher off.
- Next, you need to remove the drain hose and keep a pan or dish under the hose end as you do this, as a little residual water will inevitably spill out.
- Make a solution of equal parts baking soda and vinegar and pour it down the drain hose.
- Leave it for 10-15 minutes to loosen whatever debris is stuck there.
- Rinse it through with hot water and then re-install the hose.
It’s a good idea to run a quick wash cycle to flush any remaining cleaning solution out of the drain hose.
2. Clean the Filter
The next step in the cleaning process is to clean the cylindrical filter. This should be done every couple of weeks, but the good news is that it’s a very easy process.
- The filter is located at the bottom of the dishwasher, so you’ll need to remove the bottom tray to gain access to it.
- Twist and pull on the filter to remove it.
- Clean it thoroughly; sometimes, running it under water will do the trick. If it’s a bit more stuck on, you can use a sponge or soft brush and some warm soapy water to clean it.
- Re-install the now clean filter
3. Remove the Knock-Out Plug
If a technician hasn’t removed the garbage disposal knock-out plug at the time of installation, then you will need to do this yourself.
All you need to do is take a regular screwdriver and hammer, place the screwdriver tip onto the knock-out plug, and gently tap it a few times to dislodge the knock-out plug.
Discard the plug and re-install the garbage disposal; the excess water will drain.
4. Perform a Hard Reset
If a benign glitch has caused this error code, performing a hard reset or power cycle is the most reliable way to rectify it.
This is very easy to do; you just need to turn the dishwasher off and unplug it from the wall outlet or turn it off directly at the circuit breaker. Wait 2-3 minutes for any residual energy held in the capacitors to discharge, then plug the washer back in.
5. Unkink the Washer Hose
Carefully pull the washer away from the wall and inspect the hose for kinks or pinches. Arrange it so the water can flow through the hose properly.
Then carefully push the dishwasher back into place, being mindful not to re-introduce a new kink as you do so.
6. Seal the Siphon Connection
If water backs up into the machine, the siphon connection may not be tight enough.
You need to locate the connection point between the dishwasher and siphon and ensure a solid seal. Often it can just be tightened by hand, or if that’s not enough, there are some other methods you can use to fortify the connection point.
7. Tighten the Pump Cover
The drain pump cover is designed to cover up the drain impeller and pump, but a loose pump cover may cause the pump to flood and work ineffectively.
- Open the dishwasher door and pull the lower rack out.
- Remove the drain filter assembly by unlocking it and lifting it out.
- The drain pump cover is located underneath this in the sump, and you will see the locking tab, which keeps it in place.
- If it’s broken, replace it with a new pump cover. Otherwise, you can just push the loose impeller cover back into place to re-seal the pump cover.
Preventing the Bosch Dishwasher Error Code E24
Now that things are back in working order, you may wonder how you can stop this issue from coming back in the future.
All you need to do is keep the machine clean by removing and cleaning the filter every few weeks. This will massively reduce the debris that can make it into the drain hose and keep your dishwasher clean and functional for years to come!
Adrian is an ISCET licensed professional that has completed the National Appliance Service Technician Certification Exam and has the expertise to diagnose and repair any appliance. He is well-versed in the latest technologies and techniques and is always up-to-date on the latest industry standards.
